National Id
Site name
Persina Nature Park, protected site "Kalimok-Brashlen"
The project was carried out in the period 2002 – 2008 by the Ministry of the Environment and Water in Bulgaria and the main donor was the Global Environment Facility (GEF). The performance was the restoration of two wetlands along Danube River by construction of engineering facilities, including sluices, channels, dykes to protect the adjacent land, as well as access roads. The project aimed to enable water flow into former wetlands, provide options for controlled flooding, optimized trapping of nutrient elements, and restoration of biodiversity and fish populations.
Light or indepth?
The in-depth description of the case study
Северен централен (Severen tsentralen)
RBD code
Data provider
Jovanka Ignjatovic REC
NWRM(s) implemented in the case study
Climate zone
cool temperate dry
Mean rainfall
Mean rainfall unit
Average temperature
Mean evaportranspiration
Mean evaportranspiration unit
Mean runoff
Mean runoff unit
600 - 750 mm
Average runoff coefficient
Case Study Info
Depth groundwater
Average slope range
Monitoring impacts effects
Monitoring location
Edge of Field/Plot
Administrative annual costs
Administrative annual cost information
Protected sites management planning, Capacity building, Monitoring
Monitoring parameters
Biodiversity, surface and ground water quality
Performance impact estimation method
Catchment outlet
Performance impact estimation information
N and P monitoring on annual basis. Biodiversity database carried out in the period 2001-2008
Application scale
Installation date
Performance timescale
11 - 20 years
Area (ha)
Design capacity description
50-60 days flood anually; The technical design of the project for Persina site includes inflow and outlet facilities with the following dimensions:
- 3 Inflow sluices 2.0/1.5 m and maximum runoff capacity 17.3 m3/s.
- 1 Outlet facility †“double sluice with dimensions 2 x 2.0/1.5 m and max. capacity 34.6 m3/s.
The technical design for Kalimok-Brushlen includes inflow and outlet facilities with the following dimensions:
- Inflow sluice with dimensions 2x1.5/1.00 m and max. capacity 18.6 m3/s
- Inflow sluice 2.0/1.5 m and capacity 20.5 m3/s.
- Outlet 2 x2.0/1.5 m and capacity 37.3 m3/s.
Possible appearance of disease because of mosquitoes
Favourable preconditions
Due to the hydrogeological conditions of the sites, parts of the wetlands continued to exist and have a high potential for restoration.
Peak flow rate
Public consultation
Contractural arrangements
Design contractual arrangement
Arrangement type Responsibility Role Comments Name
Contractual agreement
Global Environmental Facility Trust Fund Grant Agreement
Design consultation activity
Activity stage Key issues Name Comments
Public and media outreach
The aproach ensure public awarenes
Training and consulting of local
Local consulting in Belene, 30th of June, 2002, 25 participants and in Slivo Pole, 31th of June, 20.
Project promotion
Public support as well as support of public institutions and donor community in the country.
Environmental education
Design land use change
Land use change type
Design authority
Authority type Role Responsibility Name Comments
National water authority
Government of Bulgaria, Ministry of Environment and Water
and Financing
Local water authority
Persina NP Directorate
Long-term maintenance and monitoring of impacts
Regional / sub-national water authority
Dabube River Basin Directorate
Monitoring of WFD compliant quality elements, integration into RBMP
Key lessons
When plenty of stakeholders are involved, it would be appropriate to provide longer groundwork. Participatory approaches to wetland restoration design were critical for Project success, which hinged on changing people's perceptions of wetlands, and gaining the full support for restoration among authorities and stakeholders. PA Local Consultative Councils and public awareness campaigns effectively supported stakeholder involvement.

Controlled restoration is a step in the right direction and is allowing large- scale experimentation and studying of nutrient trapping processes.

Solid knowledge on the baseline and the desired ecosystem status should be embedded early in project design phase.
Financing difficulties
Success factor(s)
Success factor type Success factor role Comments
Attitude of relevant stakeholders

The intensive stakeholder involvement during design and implementation created strong ownership and sustainable Project outcomes

Financing possibilities

The overall co-financing proveded by government substantially exceeded amounts agreed at appraisal.

Existing staff and consultant knowledge

Bank and Gobernment cooperation was in timely attention to critical implementation issues.

Attitude of relevant stakeholders

Established local Park administration, responsible for the maintenance and future operation of the NWRM

Financing type Comments
National funds
Government of Bulgaria
National funds
Austrian Government
Barrier type Barrier role Comments
Attitude of the public
secondary barrier
Administrative difficulties, related to land ownership / statute resulted in project delay
Limited staff and consultant knowledge
secondary barrier
Difficulties with technical design due to insufficient national expertise in wetlands restoration
secondary barrier
Not defined target ecosystem status (favorable conservation status) at the project start
Driver type Driver role Comments
Legal obligations
main driver
The Environmental Program for the Danube River Basin as a `preemptive measure to prevent river Danube and Black Sea water pollution from reaching catastrophic proportions`
Legal obligations
main driver
Danube Pollution Reduction program (DRP)
Financing share
Financing share type Share Comments
European funds
National funds
Policy description
Over the years, the wetlands and floodplain have been drained or dyked to create arable land and to reduce malarial mosquito habitats. Now the wetlands area is about 10 percent of its original size at the turn of the century, reducing the capacity of its ecological function of water purification.
Part of wider plan
Policy target
Target purpose
Pollutants Removal
Improved Biodiversity
Increase Water Storage
Policy pressure
Pressure directive Relevant pressure
Policy area
Policy area type Policy area focus Name Comments
Policy impact
Impact directive Relevant impact
Policy wider plan
Wider plan type Wider plan focus Name Comments
Environment & Biodiversity
GEF Black Sea/Danube Strategic Partenrship-Nutrient Reduction Investment fund
Bulgaria's strategy for nutrient reduction, biodiversity and agriculture and rural development.
Policy requirement directive
Requirement directive Specification
Direct benefits information
Protection of the Danube river basin from nutrient pollution inccreasing and improving the water quality.
Ancillary benefits information
Increased economic beneffits due to fishery and biomass production and farming practices.
Costs investment
Costs investment information
Cost of restoration of Belene Island and K/B Marshes
Costs capital
Costs land acquisition
Costs land acquisition unit
€ (total value)
Costs operation maintenance
Costs operation maintenance
Operation of the facilities for regular flooding
Costs total
Costs total information
Cost of restoration of Belene Island and K/B Marshes and other additional sites
Economic costs additional
Information on Economic costs additional
Restoration of additional sites
Ecosystem improved biodiversity
Information on Ecosystem improved biodiversity
As water quality improves, local species have already benefited. Fish have returned to spawn and with the retorned fish spawn, also have a return of an increase of rare bird species such as the white-tailed eagle and the Dalmatian pelican.
Ecosystem provisioning services
Information on Ecosystem provisioning services
Tourism development in the region, new employment opportunities, economic benefits due to fishery and biomass production.
Ecosystem impact climate regulation
No information available
Information on Ecosystem impact climate regulation
No info available
Retained water
Retained water unit
mio m3/month
Information on retained water
In total both sites
Runoff reduction
Information on increased water storage
The space for flooding is wider, with the selected situation of the dykes, with an area of 4035ha
Runoff reduction unit
% Percent
Information on runoff reduction
Runoff control by controlled flooding regime of the restored wetlands.
Peak flow rate reduction
Peak flow rate reduction unit
Information on Increased Evapotranspiration
Evaporation in the wetland will be as max about 1 m3/sec.
Information on Restoring hydraulic connections
80% of the former wetland restored
Water quality overall improvements
Positive impact-WQ improvement
Information on Water quality overall improvements
NWRM has impacted the overall water quality by nutrient reduction and capture (N, P) and capture of organic pollutants. Preliminary analysis indicates that the total nutrients reduction could reach 2.200 tons/year nitrogen and 284 tons/year phosphorus.
Soil quality overall soil improvements
N/A info
Information on Soil quality overall soil improvements
No info available